1. Field of the Invention
The present invention relates to an image forming apparatus having a scanner portion and a printer portion. More specifically, the present invention is applicable to a digital copying machine, a facsimile apparatus, a multifunctional printer (MFP) or the like which is divided into a scanner portion for reading an original and a printer portion for forming an image on a sheet.
2. Description of the Related Art
Conventionally, as an image forming apparatus such as a digital copying machine, a facsimile apparatus, or a multifunctional printer (MFP) formed by combining such an apparatus with a printer, there has been known one which is divided into units including a printer portion and a scanner portion. To facilitate the operation of the scanner portion, the scanner portion is usually installed above the printer portion. The printer portion has an image forming portion for forming an image on a sheet material, and the scanner portion has an image reading portion for reading an image of an original.
In such an image forming apparatus, in order to facilitate operations such as maintenance, sheet jam clearance, and replacement of process cartridges, there is adopted a construction in which the scanner portion, which is on the upper side, is rotated so as to be opened and closed with respect to the printer portion, which is on the lower side.
On the backside of the apparatus, and between the printer portion and the scanner portion, there is provided a cable as a conductor line for transmission and reception of electric signals. One end portion of this cable is connected to a printed board inside the scanner portion, and the other end portion thereof is connected to a printed board inside the printer portion.
Also regarding a copying machine, there is known a construction in which a sheet-through type scanner portion that has an original pressure plate equipped with an automatic document feeder (ADF) for an original is opened and closed with respect to an image forming apparatus main body having a flat bed type scanner. In such a copying machine, electric wires connecting the scanner portion and the printer portion are connected together by a cable on the backside of the apparatus, with the cable being in an exposed state.
When the cable connecting the scanner portion and the printer portion is thus exposed to the exterior of the image forming apparatus, the outward appearance of the apparatus suffers. Further, there is the possibility of the user inadvertently pulling the cable to damage the same.
As a solution to the above-mentioned problems, there is known a construction disclosed, for example, in Japanese Patent Application Laid-Open No. 2005-258025. As illustrated in FIG. 16, the image forming apparatus disclosed in Japanese Patent Application Laid-Open No. 2005-258025 has a scanner portion 100 and a printer portion 102, with the scanner portion 100 being connected to the printer portion via a hinge portion 101 so as to allow opening and closing. Inside the printer portion 102, there is provided, as an image forming unit, a process cartridge 105 including a photosensitive drum 104. Image information read by the scanner portion 100 is written to the photosensitive drum 104 by a laser exposure device as an electrostatic latent image before being developed into a toner image by the process cartridge 105. This toner image is transferred to a sheet material P supplied from a sheet material accommodating cassette 106, and is fixed to the sheet material through pressurization and heating by a fixing device 107. At the time of maintenance, the apparatus is opened by rotating the scanner portion 100 around the hinge portion 101, and access to the interior of the printer portion 102 is allowed through opening portions of the scanner portion 100 and the printer portion 102, thus enabling various operations to be conducted. The scanner portion 100 and the printer portion 102 are electrically connected by a cable 103. The cable 103 is arranged inside a cylindrical member 110 provided in the vicinity of the hinge portion 101, and cables and the like are accommodated in the image forming apparatus.
However, the image forming apparatus disclosed in Japanese Patent Application Laid-Open No. 2005-258025, in which the cable 103 is arranged inside the cylindrical member 110 in the vicinity of the hinge portion 101, involves the following problem.
Since the cable 103 is accommodated in the cylindrical member 110, which is integral with the casing, each time assembling or dismantling of the scanner portion 100 and the printer portion 102 is to be performed, it is necessary to detach the cable 103 from the cylindrical member 110. However, in the small space near the hinge portion 101, it is rather difficult to perform the operation of detaching the cable 103 from the cylindrical member 110. Further, it is necessary to perform the difficult operation of joining and removing components covering the cable 103, resulting in a rather poor workability. It should be noted, in particular, that the printer portion and the scanner portion of an image forming apparatus are formed by a very large number of components. Thus, from the viewpoint of assembly workability, there is a strong demand for a construction which allows connection via a cable of the printer portion and the scanner portion joined together after being respectively assembled as complete units.